Cancer is a generic term for a large group of diseases caused by uncontrolled growth and spread of cells that can affect any part of the body. Currently numerous treatment options are available for cancer, including chemotherapy, surgery and radiation for localised disease or a combination of said treatments. The choice of therapy depends upon the location of cancer and also the extent to which the cancer has spread at the time of diagnosis. Chemotherapy is one of the most common forms of treatment for cancer which involves use of anticancer drugs that can destroy the cancer cells. Despite continuing advances in the treatment regimens for cancer, this disease still remains one of the leading causes of death in the world, most probably for the reason that the available treatment options are associated with undesirable side effects and limited efficacy. Hence, new anticancer agents/drugs showing clinical benefits for treating cancer are needed.
There are reports of anticancer compounds such as taxol, vincristine, torreyanic acid, and camptothecin from natural resources (Natural Product Communications, 2009, 4 (11), 1513).
The marine environment, covering seventy percent of the earth's surface and ninety five percent of its tropical biosphere represents thirty four of the thirty six phyla of life and provides a fascinating variety of biodiversity exceeding that of the terrestrial environment (Life Sciences, 2005, 78, 442-453). Marine natural product bioprospecting, which is exploration, extraction and screening of biological diversity and indigeneous knowledge for commercially valuable genetic and biochemical resources, has yielded a considerable number of drug candidates (Drug Discovery Today, 2003, 8 (12), 536-544).
There have been reports of discovery of numerous pharmaceutical agents involving screening of natural products from marine organisms and microorganisms. Examples of anticancer agents originating from a marine source include citarabine, bryostatin-1, aplidine, dolastatin 10 and ET-743 (Current Opinion in Pharmacology, 2001, 1, 364-369).
A number of hexadepsipeptides are reported in the art. For example, JP09040559 discloses hexadepsipeptide class of compounds having anti-inflammatory activity which are effective against both allergic and non-allergic inflammations.
Considering that many therapeutically active compounds have been obtained from natural sources, it would be prudent to explore this area of research to obtain new compounds that can be effectively used in the treatment of diseases like cancer. The inventors of the present patent application directed their efforts to provide a novel compound which finds use in the treatment of cancer. Also provided are the methods to produce this compound by fermentation and further, effecting chemical modifications of the compound of Formula (1) to obtain its derivatives.